Humility is a posture toward God and life. It includes the concept that there are many things we don't know and many things that we cannot know in relation to God who knows all things. Above all it is a posture of trust in God rather than in ourselves.
Psalm 131:2 says, "I have stilled and quieted my soul; like a weaned child with its mother, like a weaned child is my soul within me." Humility is dependence on God, just as a young child is dependent on its mother and trusts his/her mother for one's daily needs.
We often think that the best and brightest are those who know all the answers, are self sufficient, self made and have it all together. God says not! The best and the brightest understand that a posture of humility rather than pride is what God looks for. And that is based on a posture of dependence on God rather than independence from Him.
Our hope is not in ourselves. Our wisdom comes from above. Our provision is a gift of God. As the Psalmist concludes, "put your hope in the Lord both now and forevermore. It is a life posture of humility.